{"id":"CVE-2026-55551","title":"ZAC: Missing per-zaaktype authorization on by-ID decision and process reads","summary":"ZAC is an open-source, workflow-based Common Ground component for Dutch municipal case management. Prior to 5.2.0, by-id read endpoints in `src/main/kotlin/nl/info/zac/app/zaak/ZaakRestService.kt` omit `assertPolicy`(`policyService.readZ…","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N","cvssSource":"cna","cwe":["CWE-285","CWE-639"],"vendor":"infonl","product":"dimpact-zaakafhandelcomponent","affected":["dimpact-zaakafhandelcomponent < 5.2.0"],"published":"2026-10-30","updated":"2026-10-30","sourceUpdated":"2026-10-30T16:48:51.352Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-55551","references":[{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/security/advisories/GHSA-cv9m-35q4-cxfm","label":"https://github.com/infonl/dimpact-zaakafhandelcomponent/security/advisories/GHSA-cv9m-35q4-cxfm"},{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6225","label":"https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6225"},{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6229","label":"https://github.com/infonl/dimpact-zaakafhandelcomponent/pull/6229"},{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/7b90586be658cec9fa5c98c0838636237f40931f","label":"https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/7b90586be658cec9fa5c98c0838636237f40931f"},{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/d050f247301a1bcfb867015725a693c540a06f5a","label":"https://github.com/infonl/dimpact-zaakafhandelcomponent/commit/d050f247301a1bcfb867015725a693c540a06f5a"},{"url":"https://github.com/infonl/dimpact-zaakafhandelcomponent/releases/tag/v5.2.0","label":"https://github.com/infonl/dimpact-zaakafhandelcomponent/releases/tag/v5.2.0"}],"tags":["cve.org"],"epss":0.00257,"epssPercentile":0.17523,"ingestedAt":"2026-11-05T16:24:31.090Z","slug":"CVE-2026-55551","body":"## Overview\n\nZAC is an open-source, workflow-based Common Ground component for Dutch municipal case management. Prior to 5.2.0, by-id read endpoints in `src/main/kotlin/nl/info/zac/app/zaak/ZaakRestService.kt` omit `assertPolicy`(`policyService.readZaakRechten(zaak).lezen`) authorization. `RequestAuthorizationFilter` and `hasAnyApplicationRole` require only an application role on any zaaktype, not the target case's type, while `zaak-rechten.rego` enforces the actual `zaaktype_allowed` boundary only when invoked. An authenticated low-privileged municipal user who knows a case or decision UUID can use `GET /rest/zaken/besluit/zaakUuid/{uuid}` (`listBesluitenForZaakUUID`) to read decisions including types, dates, and free-text toelichting; `GET /rest/zaken/besluit/{uuid}/historie` (`listBesluitHistorie`) to read audit old/new values; and `GET /rest/zaken/{uuid}/process-diagram` (`downloadProcessDiagram`) to read BPMN workflow state across unauthorized zaaktypes. The advisory also identifies `zaak/{uuid}/afzender` (`listAfzendersVoorZaak`) as exposing zaaktype mailbox configuration without a policy check. The search/_zoek path is correctly authorization-filtered and is not part of this by-id read cluster. This issue is fixed in version 5.2.0.\n\n## Affected\n\n- `dimpact-zaakafhandelcomponent < 5.2.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}